A tubular shaft and an instrument grip of the aforementioned kind can be releasably connected to each other by the respective coupling elements forming a coupling device, in order to form an aforementioned electrosurgical tubular shaft instrument. For this purpose, the instrument grip usually comprises a sleeve-shaped receptacle into which the tubular shaft is partially insertable and in which it is releasably lockable. By means of at least one grip element of the instrument grip, it is usually possible to act on a pulling and/or pushing force transmission element guided in the tube, which is coupled at the distal end to the tool, so that the tool can be actuated with the at least one grip element.
The tool of the tubular shaft is electrically connected to at least one electric connection line, so that the tool can be supplied with electrosurgical energy. For electrical safety reasons, the at least one connection line extends in the tube, and it can thereby also be kept away from the operating site, which improves the handling of the tubular shaft. In the known tubular shaft instruments, the at least one electric connection line as well as the at least one coupling element are introduced into the instrument grip in which the electric connection line is contacted by electric contact members. For this purpose, the instrument grip, for its part, is connected by a further electric connection line to an electric energy supply. These tubular shafts, instrument grips and, consequently, tubular shaft instruments have a relatively complicated construction as only relatively little constructional space is available for mechanical connection of the tubular shaft to the instrument grip and electric contacting of the at least one connection line in the instrument grip. With exchangeable tubular shaft systems in which a reusable instrument grip is used with one-way tubular shafts, such mechanical coupling and electric contacting in the instrument grip makes cleaning, in particular, sterilization, thereof, after operational use, difficult.
An object underlying the present invention is to provide a generic tubular shaft, a generic instrument grip and a generic tubular shaft instrument, so that the tubular shaft instrument formed by the tubular shaft and the instrument grip has a constructionally simpler design.